Method of fabricating semiconductor package

ABSTRACT

A semiconductor package of this invention achieves higher wiring densities and increases the degree of freedom of the wiring design. The semiconductor package includes a first substrate having first and second faces, and first wiring provided on the first face of the first substrate. The semiconductor package also includes a second substrate having first and second faces, and second wiring provided on the first face of the second substrate. The semiconductor package also includes a semiconductor chip connected to the first and second wiring. The first face of the first substrate faces the first face of the second substrate, and the first and second wiring intersect one another in three dimensions in an isolated state.

This is a Divisional of U.S. application Ser. No. 11/492,220, filed Jul.25, 2006, now U.S. Pat. No. 7,474,007, and allowed on Sep. 29, 2008, thesubject matter of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a semiconductor package and a method offabricating same and, more particularly, to a TCP (tape carrier package)structure and a method of fabricating same.

2. Description of the Related Art

As the density of ICs increases, there is also a tendency for the numberof wires in the semiconductor package to increase. Accordingly, there isa great demand for thinner and smaller semiconductor packages.Currently, the TAB (tape automated bonding) structure, which allows asemiconductor package to be made thinner than a flat package, is beingdeveloped and used in order to attempt the increased IC density on thesubstrate. A TAB-created package is known as a TCP, and permitshigh-density surface mounting. The TAB structure is adopted in an LCD(Liquid Crystal Display), for example.

However, there are limits in establishing high-density metal wiring evenwhen the TCP is employed.

Single-layer wiring structures are also faced by wiring design (I/Oterminal design) restrictions.

SUMMARY OF THE INVENTION

One object of the present invention is to provide a semiconductorpackage that achieves higher wiring densities and increases the degreeof freedom of the wiring design.

According to a first aspect of the present invention, there is provideda semiconductor package that includes a first substrate having first andsecond faces. The semiconductor package also includes first wiringprovided on the first face of the first substrate. The semiconductorpackage also includes a second substrate having first and second faces.The semiconductor package also includes second wiring provided on thefirst face of the second substrate. The semiconductor package alsoincludes a semiconductor chip coupled to the first and second wiring.The first face of the first substrate faces the first face of the secondsubstrate. The first and second wiring intersect each otherthree-dimensionally in an isolated (insulated) state.

Sheet-like substrates made of an insulating material, for example, canbe used for the first and second substrates. The first and second wiringcan be molded with a metallic electrically conductive material, forexample. An insulating material may be placed between the first andsecond wiring in order to isolate (insulate) the first wiring from thesecond wiring. Alternatively, spacing can be used to insulate the firstand second wires from each other.

Preferably, both or either one of the first wiring and second wiring hasrecesses in the position(s) of intersection(s) between the first andsecond wiring. Preferably, at least one of the first and second wiringis bent in an S-shape or Z-shape and the bent portion of the first orsecond wiring intersects the other wiring.

Preferably, the first substrate is a TCP (tape carrier package) tapecarrier and the second substrate is a COF (chip-on-film) film carrier.In this case, the first and second wires are inner leads.

According to a second aspect of the present invention, there is provideda method of fabricating a semiconductor package. The fabrication methodincludes forming a plurality of first inner leads on a first face of aTCP tape carrier. The fabrication method also includes connecting asemiconductor chip to the first inner leads. The fabrication method alsoincludes forming at least one second inner lead on a first face of a COFfilm carrier. The fabrication method also includes overlapping the tapecarrier and the film carrier such that the first face of the tapecarrier faces the first face of the film carrier and such that the firstand second inner leads intersect each other three-dimensionally in anisolated (insulated) state.

The semiconductor package fabrication method of this invention mayfurther include forming recesses in at least the first or second innerleads in positions of intersections with the other inner leads.

Preferably, a recess is formed in each of the first inner leads in aposition of intersection with the corresponding second inner lead, andthe tape carrier and the film carrier overlap such that the first andsecond inner leads intersect one another on a one-to-one basis.

Preferably, recesses are formed in the first inner leads in positions ofintersections with one of the second inner leads, and the tape carrierand the film carrier overlap such that this second inner lead intersectsmore than one first inner lead.

The semiconductor package fabrication method may further include bendingat least the first or second inner leads in an S-shape or a Z-shape.Preferably, the bent portions of the first or second inner leadsintersect the other inner leads.

Preferably, a recess is formed in each of the first inner leads inpositions of intersections with the second inner lead, the second innerlead has an X-shaped portion, and the tape carrier and the film carrieroverlap such that the X-shaped portion of the second inner lead facesthe recesses of the first inner leads.

Preferably, a recess is formed in each of the first inner leads and eachof the second inner leads in a position of intersection, and the tapecarrier and the film carrier overlap such that the recesses face oneanother.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a COF film carrier used for a semiconductorpackage according to a first embodiment of the present invention;

FIG. 2 is a cross-sectional view taken along the line 2-2 in FIG. 1;

FIG. 3 is an enlarged plan view of part of FIG. 2 (the area surroundedby a broken-line ellipse);

FIG. 4A is a cross-sectional view taken along the line 4A-4A in FIG. 3;

FIG. 4B is a cross-sectional view taken along the line 4B-4B in FIG. 3;

FIG. 5 is a plan view of the TCP tape carrier used for the semiconductorpackage according to the first embodiment;

FIG. 6 is a cross-sectional view taken along the line 6-6 in FIG. 5;

FIG. 7 is an enlarged plan view of a portion of FIG. 6 (area surroundedby a broken-line ellipse);

FIG. 8A is a cross-sectional view taken along the line 8A-8A in FIG. 7;

FIG. 8B is a cross-sectional view taken along the line 8B-8B in FIG. 7;

FIG. 9 is a partial plan view of a semiconductor chip that is bonded toa TCP tape carrier used for the semiconductor package according to thefirst embodiment;

FIG. 10 is a cross-sectional view taken along the line 10-10 in FIG. 9;

FIG. 11 is a partial plan view of a COF film carrier that is mountedafter bonding the semiconductor chip to the TCP tape carrier accordingto the first embodiment;

FIG. 12A is a cross-sectional view taken along the line 12A-12A in FIG.11;

FIG. 12B is a cross-sectional view taken along the line 12B-12B in FIG.11;

FIG. 12C is a cross-sectional view taken along the line 12C-12C in FIG.11;

FIG. 13 is a plan view of the TCP tape carrier used for thesemiconductor package according to the second embodiment of the presentinvention and shows a state where a semiconductor chip is bonded;

FIG. 14 is a cross-sectional view taken along the line 14-14 in FIG. 13;

FIG. 15 is a plan view of part of the COF film carrier used for thesemiconductor package according to the second embodiment;

FIG. 16A is a cross-sectional view taken along the line 16A-16A in FIG.15;

FIG. 16B is a cross-sectional view taken along the line 16B-16B in FIG.15;

FIG. 17 is a plan view of the principal parts of the semiconductorpackage according to the second embodiment and shows a state where asemiconductor chip is bonded to the TCP tape carrier and COF filmcarrier;

FIG. 18A is a cross-sectional view taken along the line 18A-18A in FIG.17;

FIG. 18B is a cross-sectional view taken along the line 18B-18B in FIG.17;

FIG. 18C is a cross-sectional view taken along the line 18C-18C in FIG.17;

FIG. 19 is a plan view of part of the TCP tape carrier used for thesemiconductor package according to the third embodiment of the presentinvention;

FIG. 20A is a cross-sectional view taken along the line 20A-20A in FIG.19;

FIG. 20B is a cross-sectional view taken along the line 20B-20B in FIG.19;

FIG. 21 is a plan view of part of the COF film carrier used for thesemiconductor package according to the third embodiment;

FIG. 22A is a cross-sectional view taken along the line 22A-22A in FIG.21;

FIG. 22B is a cross-sectional view taken along the line 22B-22B in FIG.21;

FIG. 23 is a partial plan view of a semiconductor chip that is bonded toa TCP tape carrier shown in FIG. 19;

FIG. 24 is a cross-sectional view taken along the line 24-24 in FIG. 23;

FIG. 25 is a plan view of the principal parts of the semiconductorpackage according to the third embodiment and shows a state where asemiconductor chip is bonded to a TCP tape carrier and COF film carrier;

FIG. 26A is a cross-sectional view taken along the line 26A-26A in FIG.25;

FIG. 26B is a cross-sectional view taken along the line 26B-26B in FIG.25;

FIG. 26C is a cross-sectional view taken along the line 26C-26C in FIG.25;

FIG. 27 is a partial plan view of a semiconductor chip that is bonded toa TCP tape carrier according to the fourth embodiment of the presentinvention;

FIG. 28A is a cross-sectional view taken along the line 28A-28A in FIG.27;

FIG. 29 is a plan view of part of the COF film carrier used for thesemiconductor package according to the fourth embodiment of the presentinvention;

FIG. 30A is a cross-sectional view taken along the line 30A-30A in FIG.29;

FIG. 30B is a cross-sectional view taken along the line 30B-30B in FIG.29;

FIG. 31 is a plan view of the principal parts of the semiconductorpackage according to the fourth embodiment and shows a state where asemiconductor chip is bonded to a TCP tape carrier of FIG. 27 and COFfilm carrier of FIG. 29; and

FIG. 32A is a cross-sectional view taken along the line 32A-32A in FIG.31;

FIG. 32B is a cross-sectional view taken along the line 32B-32B in FIG.31; and

FIG. 32C is a cross-sectional view taken along the line 32C-32C in FIG.31.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention will be described hereinbelow. Inthe embodiments, three-dimensional wiring is implemented by a newpackage structure that combines a TCP and a COF.

First Embodiment

Referring to FIGS. 1, 2, 3, 4A and 4B, a COF film carrier 10 used forthe semiconductor package according to the first embodiment of thepresent invention will be described.

As shown in FIG. 1, the COF film carrier 10 has an input terminal 18 andan output terminal 20 that include metal wiring material formed on asubstrate (film) 12. The substrate 12 has a thickness of about 38 μm. Anopen portion 24 for mounting the semiconductor chip 60 (FIG. 9) isformed on the substrate film 12. Areas of the metal wiring materialother than those areas for the input terminal 18, output terminal 20,and inner lead 26 (FIG. 2) are protected by a resist 14. The overallconstitution (except the structure of the inner lead) of the COF filmcarrier shown in FIG. 1 is also applied in the same way to the second tofourth embodiments which will be described later.

FIG. 2 shows an area 16 surrounded by an ellipse indicated by the brokenline in FIG. 1. Metal wiring 18, 20, 26 (FIG. 1) is directly formed onthe substrate 12 by casting and plating, for example. The thickness ofthe metal wiring 18, 20, 26 is about 8 μm and the thickness of theresist 14 is about 25 μm.

As shown in FIG. 3, the inner lead 26 is molded in an S-shape or steppedshape with a shape having a linear portion that extends linearly towardthe open portion 24 and a bent portion (oblique portion) 26 a. It shouldbe noted that the shape of the inner lead 26 may be another shape suchas a Z shape. The bent portion 26 a of the inner lead 26 can be moldedby general patterning. A wiring pattern of the inner lead 26 with thebent portion 26 a is prepared beforehand and the pattern is used to formthe inner lead 26 on the substrate 12. Such a method is an example andis also applicable to the second to fourth embodiments.

FIG. 5 is a plan view of a TCP tape carrier 40 used for thesemiconductor package according to the first embodiment. FIG. 6 is across-sectional view taken along the line 6-6 in FIG. 5. FIG. 7 is anenlarged plan view showing part of FIG. 6 (area surrounded by theellipse defined by the broken line). FIG. 8A is a cross-sectional viewtaken along the line 8A-8A in FIG. 7 and FIG. 8B is a cross-sectionalview taken along the line 8B-8B in FIG. 7. As shown in FIG. 5, the TCPtape carrier 40 has an input terminal 48 and an output terminal 50 on asubstrate (tape) 42. The input and output terminals 48 and 50 are madefrom a metal wiring material. The substrate 42 has a thickness of about75 μm. An open portion 54 for mounting the semiconductor chip 60 (FIG.9) is formed on the substrate 42. The metal wiring material other thanthose areas for the input terminal 48, output terminal 50, and innerlead 56 is protected by a resist 44. The overall constitution of the TCPtape carrier shown in FIG. 5 is also applied in the same way to thesecond to fourth embodiments. FIG. 6 shows an area 46 surrounded by anellipse formed by the broken line in FIG. 5. Metal wiring 48, 50, 56 isbonded to the substrate 42 by adhesive 58. The thickness of the metalwiring 48, 50, 56 is about 15 μm, the thickness of the resist 44 isabout 25 μm, and the thickness of the adhesive 58 is about 12 μm.

As shown in FIGS. 6, 7, 8A and 8B, a recess 56 a is formed in each ofthe inner leads 56. The inner leads 56 extend linearly to the openportion 54. The positions of the recesses 56 a correspond with (orintersect) the bent portions 26 a of the inner leads 26 of the COF filmcarrier 10 in the subsequent assembly step. The recesses 56 a arepreferably located above the substrate 42. If the recesses 56 a areformed in a position of protrusion from the substrate 42 (i.e., if therecesses are outside the substrate when viewed from the top), there isthe risk that the positions of the intersections between the inner leads26 and the recesses 56 a in the perpendicular direction (verticaldirection in FIG. 6) will become unstable.

When molding the recesses 56 a in the inner leads 56, one of threemethods may be used. A first method involves creating a diecorresponding with the recesses 56 a and molding the recesses 56 a inthe inner leads 56 by means of pressing. A second method involvesmolding a pattern that includes the inner leads 56 when creating thepattern of the TCP tape carrier 40. Then, the recesses 56 a are formedby removing only the mask of the areas corresponding with the recesses56 a and etching these areas. A third method involves preparing twopieces (sheets) of metal wire material and forming a metal wire bypatterning the first sheet of metal wire material. Then, the secondmetal wire sheet is placed on the first metal wire sheet by using anelectrically conductive adhesive, and the patterning is performed. Whenthe second metal wire sheet is placed on the first metal wire sheet andpatterned, a wiring pattern is formed excluding the areas correspondingwith recesses 56 a. It should be noted that these three methods areexamples and are also applicable to the second to fourth embodiments. Inthe case of the third embodiment, the above-described three methods canalso be applied to the formation of the recesses in the inner leads ofthe COF film carrier 10.

FIG. 9 is a partial plan view of a state where a semiconductor 60 isbonded to the TCP tape carrier 40. This is the inner lead bonding. FIG.10 is a cross-sectional view taken along the line 10-10 in FIG. 9. Bumps62 are formed on the semiconductor chip 60 and the free ends of theinner leads 56 are connected by means of thermal bonding to the bumps62.

FIG. 11 is a partial plan view of a state where the COF film carrier 10is mounted after bonding the semiconductor chip 60 to the TCP tapecarrier 40. For the sake of description, FIG. 11 shows the COF filmcarrier 10 with only the inner leads 26, and other elements are omitted.FIG. 12A is across-sectional view taken along the line 12A-12A in FIG.11, FIG. 12B is a cross-sectional view taken along the line 12B-12B inFIG. 11, and FIG. 12C is a cross-sectional view taken along the line12C-12C in FIG. 11. After the semiconductor chip 60 is bonded to the TCPtape carrier 40, the COF film carrier 10 shown in FIGS. 1 to 4B ismounted in an upside down state. The ends of the inner leads 26 of theCOF film carrier 10 are connected by thermal bonding to the bumps 62formed on the semiconductor chip 60. As a result, the bent portions 26 aof the inner leads 26 of the COF film carrier 10 cross, on a one-to-onebasis, the recesses 56 a in the inner leads 56 of the TCP tape carrier40. The linear portions of the inner leads 56 and 26 are arranged spacedapart from one another in a parallel state. The inner leads 56 and 26are isolated (insulated) by a space in the recesses 56 a of the innerleads 56.

When the TCP tape carrier 40 and COF film carrier 10 are bonded to oneanother, an adhesive is applied to the surface of the resist 44beforehand, and the resist is bonded to the resist by means of thermalbonding during the inner lead bonding step of the COF film carrier 10.The adhesive is preferably of an insulating material. It should be notedthat if bonding of only the resists is executed, the adhesive need notnecessarily be insulating.

Alternatively, the TCP tape carrier 40 and COF film carrier 10 can bebonded to one another by means of the injection of resin as is performedin a general resin sealing step for a COF assembly. That is, aftercausing the TCP tape carrier 40 and COF film carrier 10 to overlap oneanother as shown in FIG. 11, the TCP tape carrier 40 and COF filmcarrier 10 are vertically inverted and resin is injected between the COFfilm carrier 10 and semiconductor chip 60. The resin is injected betweenthe resist 44 of the TCP tape carrier 40 and the resist 14 of the COFfilm carrier 10 and then cured. The injection resin is the insulatingresin.

The semiconductor package according to this embodiment achieves higherwiring densities and increases the degree of freedom of the wiringdesign by implementing the three-dimensional crossing of the innerleads.

Second Embodiment

FIG. 13 is a plan view of the TCP tape carrier used for thesemiconductor package according to the second embodiment of the presentinvention and shows a state where a semiconductor chip 60 is bonded.FIG. 14 is a cross-sectional view taken along the line 14-14 in FIG. 13.In this embodiment, the same reference numerals and symbols are assignedto the elements that are the same as or correspond with the firstembodiment and repetitive descriptions are avoided.

The structure of the TCP tape carrier 40 according to this embodiment isbasically the same as that of the TCP tape carrier 40 of the firstembodiment. Specifically, the structure of FIGS. 5 and 6 can be adopted.The input terminal 48 and output terminal 50 are formed on a substrate(tape) 42. The input and output terminals are made from a metal wiringmaterial. The substrate 42 has a thickness of about 75 μm. An openportion 54 for mounting the semiconductor chip 60 is formed on thesubstrate 42. Areas of the metal wiring material other than those areasfor the input terminal 48, output terminal 50, and inner lead 156 areprotected by the resist 44.

Like the first embodiment, metal wiring 48, 50, 156 is bonded on thesubstrate 42 by an adhesive 58. The thickness of the metal wiring 48,50, 156 is about 15 μm, the thickness of the resist 44 is about 25 μm,and the thickness of the adhesive 58 is about 12 μm.

As shown in FIGS. 13 and 14, a recess 156 a is formed in each of theinner leads 156. The inner leads 156 extend linearly to the open portion54. The positions of the recesses 156 a correspond with (or intersect)the bent portion 126 a of the inner lead 126 of the COF film carrier inthe subsequent assembly step. The recesses 156 a are preferably locatedabove the substrate 42. If the recesses 156 a are formed in a positionof protrusion from the substrate 42, there is the risk that thepositions of the intersections between the inner leads 126 and therecesses 156 a in the perpendicular direction (vertical direction inFIG. 14) will become unstable.

Like the first embodiment, bumps 162 are formed on the semiconductorchip 60. The ends of the inner leads 156 are connected by thermalbonding to the bumps 162.

FIG. 15 is a plan view of part of the COF film carrier used for thesemiconductor package according to the second embodiment. FIG. 16A is across-sectional view taken along the line 16A-16A in FIG. 15, and FIG.16B is a cross-sectional view taken along the line 16B-16B in FIG. 15.The COF film carrier has an input terminal and an output terminal formedon a substrate (film) 12. The input and output terminals are made from ametal wiring material (not illustrated). The substrate 12 has athickness of about 38 μm. An open portion 24 for mounting thesemiconductor chip 60 is formed on the substrate 12. Areas of the metalwiring material other than those areas for the input terminal, outputterminal, and inner leads 126 and 128 are protected by the resist 14.

The metal wiring 126, 128 and other metal wiring are directly formed onthe substrate 12 by casting and plating, for example. The thickness ofthe metal wiring is about 8 μm and the thickness of the resist 14 isabout 25 μm.

As shown in FIG. 15, the inner lead 126 is molded in an S-shape orstepped shape. The inner lead 126 has a linear portion that extendslinearly toward the open portion 24 and a bent portion (oblique portion)126 a. It should be noted that another shape such as a Z shape can alsobe adopted as the shape of the inner lead. In this embodiment, the innerlead 126 intersects a plurality of inner leads 156 of the TCP tapecarrier.

FIG. 17 is a plan view of the principal parts of the semiconductorpackage according to the second embodiment and shows a state where asemiconductor chip 60 is bonded to the TCP tape carrier and COF filmcarrier. For the sake of description, FIG. 17 shows the COF film carriertogether with only the inner lead 126, and other elements are omitted.FIG. 2018A is a cross-sectional view taken along the line 18A-18A inFIG. 17, FIG. 18B is a cross-sectional view taken along the line 18B-18Bin FIG. 17, and FIG. 18C is a cross-sectional view taken along the line18C-18C in FIG. 17. After bonding the semiconductor chip 60 to the TCPtape carrier, the COF film carrier shown in FIGS. 15, 16A and 16B ismounted in an upside down state. The end of the inner lead 126 of theCOF film carrier is connected through thermal bonding to the bump 62formed on the semiconductor chip 60. Here, the bent portion 126 a of theinner lead 126 of the COF film carrier crosses the recesses 156 a formedin the inner leads 156 of the TCP tape carrier. The inner leads 156 and126 are isolated by a space in the recesses 156 a of the inner leads156.

The same method as that used in the first embodiment can be adopted asthe method for bonding the TCP tape carrier 40 to the COF film carrier10.

As described earlier, the semiconductor package of the second embodimentcan achieve the same advantages as the first embodiment. Also, thesemiconductor package of the second embodiment can allow the change inthe inner lead arrangement in an easy manner. Thus, it is possible toprovide a semiconductor package which has different input and outputterminal arrangements by using the same semiconductor chip.

Third Embodiment

FIG. 19 is a plan view of part of the TCP tape carrier used for thesemiconductor package according to the third embodiment of the presentinvention. FIG. 20A is a cross-sectional view taken along the line20A-20A in FIG. 19 and FIG. 20B is a cross-sectional view taken alongthe line 20B-20B in FIG. 19. In this embodiment, the same referencenumerals and symbols are assigned to the elements that are the same asor correspond with the first and second embodiments, and repetitivedescriptions are avoided.

The TCP tape carrier used in this embodiment is basically the same asthat used in the first embodiment. Specifically, the TCP tape carrierhas an input terminal and output terminal on the substrate (tape) 42.The input and output terminals are made from a metal wiring material(not illustrated). The substrate has a thickness of about 75 μm. An openportion 54 for mounting the semiconductor chip 60 is formed on thesubstrate 42. Areas of the metal wiring material other than those areasfor the input terminal, output terminal, and inner leads 56 areprotected by the resist 44.

Metal wiring 48, 50, 56 is bonded to the substrate material 42 byadhesive 58. The thickness of the metal wiring 48, 50, 56 is about 15μm, the thickness of the resist 44 is about 25 μm, and the thickness ofthe adhesive 58 is about 12 μm. A recess 56 a is formed in each of theinner leads 56. The inner leads 56 extend linearly to the open portion54. The positions of the recesses 56 a correspond with (intersect) thebent portions 226 a of the inner leads 226 of the COF film carrier inthe subsequent assembly step. The recesses 56 a are preferably locatedabove the substrate 42. When the recesses 56 a are formed in a positionof protrusion from the substrate 42, there is the risk that thepositions of the intersections between the inner leads 226 and therecesses 56 a in the perpendicular direction (vertical direction in FIG.20A) will become unstable.

FIG. 21 is a plan view of part of the COF film carrier used for thesemiconductor package according to the third embodiment. FIG. 22A is across-sectional view taken along the line 22A-22A in FIG. 21 and FIG.22B is a cross-sectional view taken along the line 22B-22B in FIG. 21.The COF film carrier has an input terminal and output terminal on asubstrate (film) 12. The input and output terminals are made from ametal wiring material (not illustrated). The substrate 12 has athickness of about 38 μm. An open portion 24 for mounting asemiconductor chip 60 is formed on the substrate 12. Areas of the metalwiring material other than those areas for the input terminal, outputterminal, and inner leads 226 are protected by the resist 14.

The metal wiring 18, 20, 226 is directly formed on the substrate 12 bycasting and plating, for example. The thickness of the metal wiring 18,20, 226 is about 8 μm and the thickness of the resist 14 is about 25 μm.

As shown in FIG. 21, the inner leads 226 are molded in an S-shape orstepped shape. Each inner lead 226 has a linear portion that extendslinearly toward the open portion 24 and a bent portion (oblique portion)226 a. It should be noted that the shape of the inner lead may beanother shape such as a Z shape. A recess 226 b is formed in the bentportion 226 a of each inner lead 226. In this embodiment, the recesses56 a and 226 b are formed in both the TCP inner leads 56 and the COFinner leads 226, and the recesses 56 a overlap the recesses 226 b sothat the recesses 56 a and 226 b intersect one another with a gap.

FIG. 23 is a partial plan view of a state where a semiconductor chip isbonded to a TCP tape carrier (FIG. 19) according to the thirdembodiment. FIG. 24 is a cross-sectional view taken along the line 24-24in FIG. 23. Bumps 62 are formed on the semiconductor chip 60 and theends of the inner leads 56 are connected by means of thermal bonding tothe bumps 62.

FIG. 25 is a plan view of the principal parts of the semiconductorpackage according to the third embodiment and shows the semiconductorchip 60 bonded to a TCP tape carrier and COF film carrier. For the sakeof description, FIG. 25 shows the COF film carrier 10 together with theinner leads 266 only. Other elements are omitted. FIG. 26A is across-sectional view taken along the line 26A-26A in FIG. 25, FIG. 26Bis a cross-sectional view taken along the line 26B-26B in FIG. 25, andFIG. 26C is a cross-sectional view taken along the line 26C-26C in FIG.25. After the semiconductor chip 60 is bonded to the TCP tape carrier40, the COF film carrier 10 shown in FIGS. 21 and 22 is mounted in anupside down state. The ends of the inner leads 226 of the COF filmcarrier are connected by thermal bonding to the bumps 62 formed on thesemiconductor chip 60. Here, the bent portions 226 a (or the recesses226 b) of the inner leads 226 of the COF film carrier cross, on aone-to-one basis, the recesses 56 a in the inner leads 56 of the TCPtape carrier. The linear portions of the inner leads 56 and 226 arearranged spaced apart from one another in parallel within the sameplane. The inner leads 56 are isolated from the inner leads 226 by aspace in the recesses 56 a of the inner leads 56.

The same method as that used in the first embodiment can be adopted asthe method for bonding the TCP tape carrier 40 and COF film carrier 10to one another.

As described above, the semiconductor package according to thisembodiment has the recesses 56 a and 226 a which spacedly mesh with oneanother. Therefore, in comparison with the first embodiment, it ispossible to provide a semiconductor package that is thin and permits areduction in assembly defects caused by the contact between the wiringmaterial.

Fourth Embodiment

FIG. 27 is a partial plan view showing the semiconductor chip 60 bondedto a TCP tape carrier according to the fourth embodiment of the presentinvention. FIG. 28A is a cross-sectional view taken along the line28A-28A in FIG. 27. In this embodiment, the same reference numerals andsymbols are assigned to the elements that are the same as or correspondwith the first to third embodiments and repetitive descriptions areavoided. The structure of the TCP tape carrier 40 according to thisembodiment is basically the same as that of the tape carrier of thesecond embodiment. The input terminal and output terminal are formed ona substrate (tape) 42. The input and output terminals are made from ametal wiring material (not illustrated). The substrate 42 has athickness of about 75 μm. An open portion 54 for mounting thesemiconductor chip 60 is formed on the substrate 42. Areas of the metalwiring material other than those areas for the input terminal, outputterminal, and inner leads 156 are protected by the resist 44.

Like the first and second embodiments, metal wiring 48, 50, 156 isbonded on the substrate 42 by an adhesive 58. The thickness of the metalwiring 48, 50, 156 is about 15 μm, the thickness of the resist 44 isabout 25 μm, and the thickness of the adhesive 58 is about 12 μm.

A recess 156 a is formed in each of the inner leads 156. The inner leads156 extend linearly to the open portion 54. The positions of therecesses 156 a correspond with (intersect) the bent portion 326 a of theinner lead 326 of the COF film carrier in the subsequent assembly step.The recesses 156 a are preferably located above the substrate 42. Whenthe recesses 156 a are formed in a position of protrusion from thesubstrate 42, there is the risk that the positions of the intersectionsbetween the inner lead 326 and the recesses 156 a in the perpendiculardirection (vertical direction in FIG. 28A) will become unstable.

Like the first and second embodiments, bumps 162 are formed on thesemiconductor chip 60. The ends of the inner leads 156 are connected bythermal bonding to the bumps 162.

FIG. 29 is a plan view of part of the COF film carrier used for thesemiconductor package according to the fourth embodiment. FIG. 30A is across-sectional view taken along the line 30A-30A in FIG. 29 and FIG.30B is a cross-sectional view taken along the line 30B-30B in FIG. 29.The COF film carrier has an input terminal and an output terminal on asubstrate (film) 12. The input and output terminals are made from awiring material (not illustrated). The substrate 12 has a thickness ofabout 38 μm. An open portion 24 for mounting a semiconductor chip 60 isformed on the substrate 12. Areas of the metal wiring material otherthan those areas for the input terminal, output terminal, and inner lead326 are protected by the resist 14.

The metal wiring 326 and other metal wiring are directly formed on thesubstrate 12 by casting and plating, for example. The thickness of themetal wiring is about 8 μm and the thickness of the resist 14 is about25 μm.

As shown in FIG. 29, the inner lead 326 has a shape with an intersectionportion 326 a and linear portions. The intersection portion 326 a formsan X-like intersection, and the linear portions extend linearly towardthe open portion 24. In this embodiment, the inner lead 326 intersectsthe seven inner leads 156 of the TCP tape carrier (FIG. 31). Theposition of the intersection portion 326 a in the inner lead 326 can besuitably changed in accordance with the wiring design.

FIG. 31 is a plan view of the principal parts of the semiconductorpackage according to the fourth embodiment and shows a state where thesemiconductor chip is bonded to the TCP tape carrier (FIG. 27) and COFfilm carrier (FIG. 29). For the sake of the description, FIG. 31 showsthe COF film carrier 10 together with the inner lead 326 only. Otherelements are omitted. FIG. 32A is a cross-sectional view taken along theline 32A-32A in FIG. 31, FIG. 32B is a cross-sectional view taken alongthe line 32B-32B in FIG. 31, and FIG. 32C is a cross-sectional viewtaken along the line 32C-32C in FIG. 31. After bonding the semiconductorchip 60 to the TCP tape carrier, the COF film carrier shown in FIGS. 29,30A and 30B is mounted in an upside down state. The ends of the innerlead 326 of the COF film carrier are connected through thermal bondingto the bumps 62 formed on the semiconductor chip 60. The bent portionhaving the intersection portion 326 a of the inner lead 326 of the COFfilm carrier is received in the recesses 156 a formed in the inner leads156 of the TCP tape carrier and crosses the inner leads 156. The innerlead 326 intersects one inner lead 156 twice. The inner leads 156 and326 are isolated by a space in the recesses 156 a of the inner leads156.

The same method as that used in the first embodiment can be adopted asthe method for bonding the TCP tape carrier 40 and COF film carrier 10to one another.

As described above, the semiconductor package according to thisembodiment does not require wiring in the open portion used to mount thesemiconductor element, unlike a conventional COF product. Therefore,this embodiment can prevent or reduce generation of voids in theinternal wiring portion in the resin sealing step.

The present invention is not limited to the above described embodiments.For example, the present invention can be applied when the TCP isconnected to another TCP. The present invention can also be applied to apackage device other than a semiconductor package. Although airisolation is employed when wiring of two layers is made to intersect inthree dimensions in the illustrated embodiments, a general insulatingmaterial may be interposed between the layers when wiring of two layersis made to intersect in three dimensions. Specifically, an insulatingresin may be injected in the intersection between the inner lead(s) ofthe TCP tape carrier 40 and the inner lead(s) of the COF film carrier10. This can improve insulation-related reliability.

This application is based on Japanese Patent Application filed on Jul.25, 2005 and the entire disclosure thereof is incorporated herein byreference.

1. A method of fabricating a semiconductor package, comprising: forminga plurality of first inner leads on a first face of a TCP (tape carrierpackage) tape carrier; connecting a semiconductor chip to the firstinner leads; forming at least one second inner lead on a first face of aCOF (chip on film) film carrier; overlapping the tape carrier and thefilm carrier such that the first face of the tape carrier faces thefirst face of the film carrier and such that the first inner leadsintersect the at least one second inner lead three-dimensionally in anelectrically insulated state; and forming recesses in at least the firstor second inner leads in positions of intersections with the other innerleads.
 2. A method of fabricating a semiconductor package, comprising:forming a plurality of first inner leads on a first face of a TCP (tapecarrier package) tape carrier; connecting a semiconductor chip to thefirst inner leads; forming at least one second inner lead on a firstface of a COF (chip on film) film carrier; and overlapping the tapecarrier and the film carrier such that the first face of the tapecarrier faces the first face of the film carrier and such that the firstinner leads intersect the at least one second inner leadthree-dimensionally in an electrically insulated state, wherein a recessis formed in each said first inner lead in a position of intersectionwith the corresponding second inner lead, and the tape carrier and thefilm carrier overlap such that the first and second inner leadsintersect one another on a one-to-one basis.
 3. The method offabricating a semiconductor package according to claim 1, whereinrecesses are formed in the first inner leads in positions ofintersections with one of the at least one second inner lead, and thetape carrier and the film carrier overlap such that the second innerlead intersects more than one said first inner lead.
 4. A method offabricating a semiconductor package, comprising: forming a plurality offirst inner leads on a first face of a TCP (tape carrier package) tapecarrier; connecting a semiconductor chip to the first inner leads;forming at least one second inner lead on a first face of a COF (chip onfilm) film carrier; overlapping the tape carrier and the film carriersuch that the first face of the tape carrier faces the first face of thefilm carrier and such that the first inner leads intersect the at leastone second inner lead three-dimensionally in an electrically insulatedstate; and bending at least the first or second inner leads in anS-shape or a Z-shape.
 5. The method of fabricating a semiconductorpackage according to claim 4, wherein the bent portions of the first orsecond inner leads intersect the other inner leads.
 6. The method offabricating a semiconductor package according to claim 1, wherein arecess is formed in each said first inner lead in positions ofintersections with the second inner lead, the second inner lead has anX-shaped portion, and the tape carrier and the film carrier overlap suchthat the X-shaped portion of the second inner lead faces the recesses ofthe first inner leads.
 7. A method of fabricating a semiconductorpackage, comprising forming a plurality of first inner leads on a firstface of a TCP (tape carrier package) tape carrier; connecting asemiconductor chip to the first inner leads; forming at least one secondinner lead on a first face of a COF (chip on film) film carrier; andoverlapping the tape carrier and the film carrier such that the firstface of the tape carrier faces the first face of the film carrier andsuch that the first inner leads intersect the at least one second innerlead three-dimensionally in an electrically insulated state, wherein arecess is formed in each said first inner lead and each said secondinner lead in a position of intersection, and the tape carrier and thefilm carrier overlap such that the recesses face one another.
 8. Amethod of fabricating a semiconductor package comprising: providing afirst substrate having a first face and a second face; forming a firstwiring on the first face of the first substrate; providing a secondsubstrate having a first face and a second face; forming a second wiringon the first face of the second substrate; providing an insulation layerbetween the first and second wiring; connecting a semiconductor chip tothe first and second wiring; and forming first and second bumps on thesemiconductor chip such that the first wiring is connected to thesemiconductor chip via the first bump and the second wiring is connectedto the semiconductor chip via the second bump, wherein the first face ofthe first substrate faces the first face of the second substrate, andthe first wiring crosses the second wiring and is electrically insulatedfrom the second wiring by the insulation layer.
 9. The method accordingto claim 8, wherein at least one of the first and second wiring isformed with a recess in a position of intersection between the first andsecond wiring.
 10. The method according to claim 8 further bending atleast one of the first and second wiring in an S-shape or Z-shape, suchthat the bent portion of the first or second wiring intersects the otherwiring.
 11. The method according to claim 8, wherein the first substrateis a TCP (tape carrier package) tape carrier and the second substrate isa COF (chip-on-film) film carrier.
 12. The method according to claim 8,wherein the first wiring includes a first inner lead and the secondwiring includes a second inner lead.
 13. A method of fabricating asemiconductor package comprising: providing a TCP (tape carrier package)tape carrier having a first face and a second face; forming a pluralityof first inner leads on the first face of the tape carrier; providing aCOF (chip-on-film) film carrier having a first face and a second face;forming at least one second inner lead on the first face of the filmcarrier; providing an insulation layer between the plurality of firstinner leads and the at least one second inner lead; connecting asemiconductor chip to the first and second inner leads; and forming aplurality of first bumps and at lest one second bump on thesemiconductor chip such that the plurality of first inner leads areconnected to the semiconductor chip via the plurality of first bumps andthe at least one second inner lead is connected to the semiconductorchip via the at least one second bump, wherein the first face of thetape carrier faces the first face of the film carrier, and the pluralityof first inner leads cross the at least one second inner lead and areelectrically insulated from the at least one second inner lead by theinsulation layer.
 14. The method according to claim 13, wherein at leastthe first or second inner leads have recesses in positions ofintersections with the other inner leads.
 15. The method according toclaim 13 further comprising forming a recess in each said first innerlead in a position of intersection with the corresponding second innerlead, wherein the first and second inner leads intersect one another ona one-to-one basis.
 16. The method according to claim 15 furthercomprising forming a plurality of recesses in the first inner leads inpositions of intersections with the second inner lead, wherein one saidsecond inner lead intersects more than one said first inner lead. 17.The method according to claim 13 further comprising bending said firstand/or second inner leads such that each said first inner lead or eachsaid second inner lead has an S-shaped or Z-shaped bent portion, andsuch that the bent portion of each said first or second inner leadintersects the other inner lead.
 18. The method according to claim 13further comprising forming a recess in each said first inner lead in aposition of intersection with the second inner lead, wherein the secondinner lead has an X-shaped portion, and the X-shaped portion faces therecesses in the first inner leads.
 19. The method according to claim 13further comprising forming a plurality of recesses in positions ofintersections in both the first and second inner leads, wherein therecesses are disposed facing one another.